Successful treatment of severe aggressiveness and explosiveness in children diagnosed as conduct disorder remains a serious challenge. The patients we wish to study have a history of chronic aggressive and explosive behavior and, after failing to respond to various outpatient treatments, including pharmacotherapy, have required hospitalization. Children diagnosed as conduct disorder with severe aggressiveness represent the largest single group of patients admitted to child psychiatric inpatient services. The majority of these patients do not respond adequately to currently available treatments and require placement in residential treatment centers. As adolescents and young adults, they tend to abuse drugs and/or alcohol and commonly will engage in antisocial behaviors and criminal acts. A more effective treatment than that now available would be of significant value in terms of both the public health and the general welfare. The loss of human potential and cost to society is immeasurable. We have replicated our earlier findings on the efficacy and safety of lithium carbonate in this type of child: lithium is statistically and clinically superior to placebo in reducing these target behaviors. However, in our ongoing study, 30% of the patient sample hand only slight or no reduction of aggressiveness and explosiveness while being treated with lithium based on the Clinical Global Consensus Rating. Also effects of lithium appeared to be weak or nonexistent for some measures (e.g.,POMS). Therefore alternate drugs have to be studied. The rationale for studying carbamazepine is twofold. First, carbamazepine has similar clinical profile to lithium, but was found to be effective is some patients who failed to respond to lithium. Second, carbamazepine is prescribed frequently to the type of child we wish to study, in the absence of strong evidence of efficacy and safety. We believe that the proposed research may further the field: treatment of severely aggressive and explosive children diagnosed as conduct disorder. The results from this study are applicable to other types of patients with severe disruptive behavior (including those who are mentally retarded. The objective of this proposal is to assess critically the efficacy and the safety of carbamazepine in 40 children, all hospitalized, ages 5 to 12 years, boys and girls, of normal intelligence, diagnosed as Conduct Disorder, Solitary Aggressive Type (DSM-III-R), and employing the DICA- R-C and DICA-R-P. This 7-week study will be double-blind and placebo controlled, using a parallel groups design. Following a 2-week placebo baseline period, children will be randomly assigned to carbamazepine or placebo treatment for 4 weeks; this will be followed by a one-week placebo period. Dosage will be individually regulated, not exceeding 1,000 mg/day. Behavioral ratings will be carried out in a variety of settings by several raters, independently employing a variety of instruments. including the Overt Aggression Scale (OAS). Drug effects will be assessed also on cognition in the laboratory, using a cognitive battery. Carbamazepine blood levels will be determined and correlated with behavioral response.